35x12.50R20 vs 37x12.50R20

37x12.50R20 is 2.0" taller than 35x12.50R20 (5.7%)

Diameter difference+5.71%diameter 35.00" → 37.00"
35x12.50R2037x12.50R20
35x12.50R2037x12.50R20Difference
Overall diameter35.00"37.00"+2.00"
Section width12.50"12.50"±0.00"
Sidewall height7.50"8.50"+1.00"
Circumference110.0"116.2"+6.3"
Revolutions per mile576545−31
Wheel diameter20"20"±0"

Speedometer

ShowsActualDiff
30 mph31.7 mph+1.7
45 mph47.6 mph+2.6
60 mph63.4 mph+3.4
70 mph74.0 mph+4.0
80 mph84.6 mph+4.6

Gear ratio to match

CurrentEquivalent
3.423.62
3.553.75
3.733.94
4.104.33

37x12.50R20 is 2.00" taller than 35x12.50R20, a +5.71% change in diameter. That is more than the 3% many tire shops use as a limit, so plan on recalibrating the speedometer and checking ABS and stability control.

Ground clearance changes by 1.00" (half the diameter change), and the tire needs 1.00" more room above it.

Both tires are the same width, 12.50".

Both fit a 20" wheel; the sidewall is 1.00" taller on 37x12.50R20.

Details: 35x12.50R20 in inches · 37x12.50R20 in inches · change sizes in the calculator

FAQ

What is the difference between 35x12.50R20 and 37x12.50R20?

37x12.50R20 is 2.00" taller (+5.71%) and 0.00" wider than 35x12.50R20.

Will 37x12.50R20 change my speedometer?

Yes, by +5.71%. When the speedometer shows 60 mph you would be going 63.4 mph.

Can I replace 35x12.50R20 with 37x12.50R20?

It is a +5.7% diameter change, larger than the common 3% guideline, so check clearance and plan to recalibrate.